Lightning strikes from a tornado in Tuscaloosa, Ala., on Monday. "Tens of thousands of customers were without power in Alabama, Mississippi and Kentucky, which did not report tornadoes but was slammed with severe storms," The Associated Press said.

Scott Black (left), Holly Boatner and Paul Flatt salvage what they can from the building where they work in Tupelo after it was destroyed by a tornado. A second day of tornadoes has caused devastation in the South.

Jodi Walker and Tabitha Russell carry a trunk from a destroyed home in Tupelo, Miss. Tuesday's storms came after tornadoes swept through Arkansas, Oklahoma and Iowa on Sunday and Monday, killing more than a dozen people.

Some news reports put the toll from the latest round of storms at 13 dead, but as is often the case with breaking stories involving natural disasters, the figures may go up or down as authorities get more information.

The storms came a day after tornadoes swept through Arkansas, Oklahoma and Iowa overnight late Sunday and early Monday, killing at least 18 people. Sunday was also the three-year anniversary of a major tornado outbreak that killed more than 250 people in six states, including Alabama and Mississippi.

The Associated Press says of affected areas waking up to devastation Tuesday: "Tens of thousands of customers were without power in Alabama, Mississippi and Kentucky, which did not report tornadoes but was slammed with severe storms. Thousands more hunkered down in basements and shelters as the National Weather Service issued watches and warnings for more tornadoes throughout the night in Alabama."

One woman was killed in a day care center she owned in Louisville, but it wasn't clear whether there were any children there at the time, officials told The Associated Press late Monday.

NWS meteorologist Brad Bryant, quoted by the Ledger, says it will be impossible to confirm how many tornadoes touched down in the state until meteorologists can get a close look at radar data and survey the areas hit. However, some weather officials think the total number could be a dozen.

In hardest-hit Tupelo, a community of about 35,000 in northeastern Mississippi, "every building in a two-block area south of U.S. Highway 78 suffered damage," officials told a reporter on the scene, according to the AP.

Alabama: 3 fatalities

Gov. Robert Bentley has declared an emergency for the state.

Winds destroyed several homes in northern Alabama, where a local coroner's office confirmed two deaths in a twister that caused extensive damage west of the city of Athens, according to the AP. The news service adds that a University of Alabama student was killed in Tuscaloosa.

Limestone County Emergency Director Rita White said more victims could be trapped in the wreckage of damaged buildings, but rescuers could not reach some areas because of downed power lines, the AP says.

A spokesman for Alabama Power tells AL.com that as of 4 a.m. local time, 11,379 customers were without power.

Tennessee: 2 fatalities

In southern Tennessee, two people were killed in a home when a tornado packing winds of 190 mph hit Monday night, Lincoln County Emergency Management Director Mike Hall told the AP.